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Nieuwenhoff MD, Nguyen HT, Niehof SP, Huygen FJPM, Verma A, Klaassen ES, Bechakra M, Geelhoed WJ, Jongen JLM, Moll AC, Vrancken AFJE, Petzold A, Groeneveld GJ. Differences in corneal nerve fiber density and fiber length in patients with painful chronic idiopathic axonal polyneuropathy and diabetic polyneuropathy. Muscle Nerve 2024. [PMID: 39056231 DOI: 10.1002/mus.28213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 07/05/2024] [Accepted: 07/14/2024] [Indexed: 07/28/2024]
Abstract
INTRODUCTION/AIMS Corneal confocal microscopy (CCM) detects small nerve fiber loss and correlates with skin biopsy findings in diabetic neuropathy. In chronic idiopathic axonal polyneuropathy (CIAP) this correlation is unknown. Therefore, we compared CCM and skin biopsy in patients with CIAP to healthy controls, patients with painful diabetic neuropathy (PDN) and diabetics without overt neuropathy (DM). METHODS Participants with CIAP and suspected small fiber neuropathy (n = 15), PDN (n = 16), DM (n = 15), and healthy controls (n = 16) underwent skin biopsy and CCM testing. Inter-center intraclass correlation coefficients (ICC) were calculated for CCM parameters. RESULTS Compared with healthy controls, patients with CIAP and PDN had significantly fewer nerve fibers in the skin (IENFD: 5.7 ± 2.3, 3.0 ± 1.8, 3.9 ± 1.5 fibers/mm, all p < .05). Corneal nerve parameters in CIAP (fiber density 23.8 ± 4.9 no./mm2, branch density 16.0 ± 8.8 no./mm2, fiber length 13.1 ± 2.6 mm/mm2) were not different from healthy controls (24.0 ± 6.8 no./mm2, 22.1 ± 9.7 no./mm2, 13.5 ± 3.5 mm/mm2, all p > .05). In patients with PDN, corneal nerve fiber density (17.8 ± 5.7 no./mm2) and fiber length (10.5 ± 2.7 mm/mm2) were reduced compared with healthy controls (p < .05). CCM results did not correlate with IENFD in CIAP patients. Inter-center ICC was 0.77 for fiber density and 0.87 for fiber length. DISCUSSION In contrast to patients with PDN, corneal nerve parameters were not decreased in patients with CIAP and small nerve fiber damage. Therefore, CCM is not a good biomarker for small nerve fiber loss in CIAP patients.
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Affiliation(s)
- Mariska D Nieuwenhoff
- Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Centre for Human Drug Research, Leiden, The Netherlands
| | - Hoang-Ton Nguyen
- Department of Ophthalmology, Amsterdam UMC location VU University Medical Center, Amsterdam, The Netherlands
| | - Sjoerd P Niehof
- Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Frank J P M Huygen
- Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | | | | | - Malik Bechakra
- Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | | | - Joost L M Jongen
- Department of Anesthesiology and Pain Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Neurology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Annette C Moll
- Department of Ophthalmology, Amsterdam UMC location VU University Medical Center, Amsterdam, The Netherlands
| | - Alexander F J E Vrancken
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Axel Petzold
- Department of Ophthalmology, Amsterdam UMC location VU University Medical Center, Amsterdam, The Netherlands
- Department of Neurology, Amsterdam UMC location VU University Medical Center, Amsterdam, The Netherlands
- Moorfields Eye Hospital, The National Hospital for Neurology and Neurosurgery and the Queen Square Institute of Neurology, UCL, London, UK
| | - Geert Jan Groeneveld
- Centre for Human Drug Research, Leiden, The Netherlands
- Department of Anesthesiology, Leiden University Medical Center, Leiden, The Netherlands
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Yang Y, Zhao B, Lan H, Sun J, Wei G. Bortezomib-induced peripheral neuropathy: Clinical features, molecular basis, and therapeutic approach. Crit Rev Oncol Hematol 2024; 197:104353. [PMID: 38615869 DOI: 10.1016/j.critrevonc.2024.104353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 03/01/2024] [Accepted: 04/10/2024] [Indexed: 04/16/2024] Open
Abstract
Bortezomib is the first-line standard and most effective chemotherapeutic for multiple myeloma; however, bortezomib-induced peripheral neuropathy (BIPN) severely affects the chemotherapy regimen and has long-term impact on patients under maintenance therapy. The pathogenesis of BIPN is poorly understood, and basic research and development of BIPN management drugs are in early stages. Besides chemotherapy dose reduction and regimen modification, no recommended prevention and treatment approaches are available for BIPN apart from the International Myeloma Working Group guidelines for peripheral neuropathy in myeloma. An in-depth exploration of the pathogenesis of BIPN, development of additional therapeutic approaches, and identification of risk factors are needed. Optimizing effective and standardized BIPN treatment plans and providing more decision-making evidence for clinical diagnosis and treatment of BIPN are necessary. This article reviews the recent advances in BIPN research; provides an overview of clinical features, underlying molecular mechanisms, and therapeutic approaches; and highlights areas for future studies.
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Affiliation(s)
- Yang Yang
- Department of Oncology, Nanjing Lishui District Hospital of Traditional Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing, China; Department of General Surgery, Changshu No. 1 People's Hospital, Affiliated Changshu Hospital of Soochow University, Changshu, China; Jiangsu Provincial Medical Innovation Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
| | - Bing Zhao
- Jiangsu Provincial Medical Innovation Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Hongli Lan
- Jiangsu Provincial Medical Innovation Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Jinbing Sun
- Department of General Surgery, Changshu No. 1 People's Hospital, Affiliated Changshu Hospital of Soochow University, Changshu, China.
| | - Guoli Wei
- Department of Oncology, Nanjing Lishui District Hospital of Traditional Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing, China; Jiangsu Provincial Medical Innovation Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China; Department of Oncology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China.
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Meregalli C, Monza L, Jongen JLM. A mechanistic understanding of the relationship between skin innervation and chemotherapy-induced neuropathic pain. FRONTIERS IN PAIN RESEARCH (LAUSANNE, SWITZERLAND) 2022; 3:1066069. [PMID: 36582196 PMCID: PMC9792502 DOI: 10.3389/fpain.2022.1066069] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 11/24/2022] [Indexed: 12/14/2022]
Abstract
Neuropathic pain is a frequent complication of chemotherapy-induced peripheral neurotoxicity (CIPN). Chemotherapy-induced peripheral neuropathies may serve as a model to study mechanisms of neuropathic pain, since several other common causes of peripheral neuropathy like painful diabetic neuropathy may be due to both neuropathic and non-neuropathic pain mechanisms like ischemia and inflammation. Experimental studies are ideally suited to study changes in morphology, phenotype and electrophysiologic characteristics of primary afferent neurons that are affected by chemotherapy and to correlate these changes to behaviors reflective of evoked pain, mainly hyperalgesia and allodynia. However, hyperalgesia and allodynia may only represent one aspect of human pain, i.e., the sensory-discriminative component, while patients with CIPN often describe their pain using words like annoying, tiring and dreadful, which are affective-emotional descriptors that cannot be tested in experimental animals. To understand why some patients with CIPN develop neuropathic pain and others not, and which are the components of neuropathic pain that they are experiencing, experimental and clinical pain research should be combined. Emerging evidence suggests that changes in subsets of primary afferent nerve fibers may contribute to specific aspects of neuropathic pain in both preclinical models and in patients with CIPN. In addition, the role of cutaneous neuroimmune interactions is considered. Since obtaining dorsal root ganglia and peripheral nerves in patients is problematic, analyses performed on skin biopsies from preclinical models as well as patients provide an opportunity to study changes in primary afferent nerve fibers and to associate these changes to human pain. In addition, other biomarkers of small fiber damage in CIPN, like corneal confocal microscope and quantitative sensory testing, may be considered.
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Affiliation(s)
- Cristina Meregalli
- School of Medicine and Surgery, Experimental Neurology Unit and Milan Center for Neuroscience, University of Milano-Bicocca, Monza, Italy,Correspondence: Cristina Meregalli
| | - Laura Monza
- School of Medicine and Surgery, Experimental Neurology Unit and Milan Center for Neuroscience, University of Milano-Bicocca, Monza, Italy
| | - Joost L. M. Jongen
- Department of Neurology, Brain Tumor Center, Erasmus MC Cancer Institute, Rotterdam, Netherlands
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Balogh M, Janjic JM, Shepherd AJ. Targeting Neuroimmune Interactions in Diabetic Neuropathy with Nanomedicine. Antioxid Redox Signal 2022; 36:122-143. [PMID: 34416821 PMCID: PMC8823248 DOI: 10.1089/ars.2021.0123] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Significance: Diabetes is a major source of neuropathy and neuropathic pain that is set to continue growing in prevalence. Diabetic peripheral neuropathy (DPN) and pain associated with diabetes are not adequately managed by current treatment regimens. Perhaps the greatest difficulty in treating DPN is the complex pathophysiology, which involves aspects of metabolic disruption and neurotrophic deficits, along with neuroimmune interactions. There is, therefore, an urgent need to pursue novel therapeutic options targeting the key cellular and molecular players. Recent Advances: To that end, cellular targeting becomes an increasingly compelling drug delivery option as our knowledge of neuroimmune interactions continues to mount. These nanomedicine-based approaches afford a potentially unparalleled specificity and longevity of drug targeting, using novel or established compounds, all while minimizing off-target effects. Critical Issues: The DPN therapeutics directly targeted at the nervous system make up the bulk of currently available treatment options. However, there are significant opportunities based on the targeting of non-neuronal cells and neuroimmune interactions in DPN. Future Directions: Nanomedicine-based agents represent an exciting opportunity for the treatment of DPN with the goals of improving the efficacy and safety profile of analgesia, as well as restoring peripheral neuroregenerative capacity. Antioxid. Redox Signal. 36, 122-143.
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Affiliation(s)
- Mihály Balogh
- Division of Internal Medicine, Department of Symptom Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Jelena M Janjic
- Graduate School of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Andrew J Shepherd
- Division of Internal Medicine, Department of Symptom Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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Kalteniece A, Ferdousi M, Azmi S, Khan SU, Worthington A, Marshall A, Faber CG, Lauria G, Boulton AJM, Soran H, Malik RA. Corneal nerve loss is related to the severity of painful diabetic neuropathy. Eur J Neurol 2021; 29:286-294. [PMID: 34570924 PMCID: PMC9292015 DOI: 10.1111/ene.15129] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 09/26/2021] [Indexed: 12/17/2022]
Abstract
Background and purpose Previously it has been shown that patients with painful diabetic neuropathy (PDN) have greater corneal nerve loss compared to patients with painless diabetic neuropathy. This study investigated if the severity of corneal nerve loss was related to the severity of PDN. Methods Participants with diabetic neuropathy (n = 118) and healthy controls (n = 38) underwent clinical and neurological evaluation, quantitative sensory testing, nerve conduction testing and corneal confocal microscopy and were categorized into those with no (n = 43), mild (n = 34) and moderate‐to‐severe (n = 41) neuropathic pain. Results Corneal nerve fibre density (p = 0.003), corneal nerve fibre length (p < 0.0001) and cold perception threshold (p < 0.0001) were lower and warm perception threshold was higher (p = 0.002) in patients with more severe pain, but there was no significant difference in the neuropathy disability score (p = 0.5), vibration perception threshold (p = 0.5), sural nerve conduction velocity (p = 0.3) and amplitude (p = 0.7), corneal nerve branch density (p = 0.06) and deep breathing heart rate variability (p = 0.08) between patients with differing severity of PDN. The visual analogue scale correlated significantly with corneal nerve fibre density (r = −0.3, p = 0.0002), corneal nerve branch density (r = −0.3, p = 0.001) and corneal nerve fibre length (r = −0.4, p < 0.0001). Receiver operating curve analysis showed that corneal nerve fibre density had an area under the curve of 0.78 with a sensitivity of 0.73 and specificity of 0.72 for the diagnosis of PDN. Conclusions Corneal confocal microscopy reveals increasing corneal nerve fibre loss with increasing severity of neuropathic pain and a good diagnostic outcome for identifying patients with PDN.
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Affiliation(s)
- Alise Kalteniece
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK
| | - Maryam Ferdousi
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK
| | - Shazli Azmi
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK
| | - Saif Ullah Khan
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK
| | - Anne Worthington
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK
| | - Andrew Marshall
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Catharina G Faber
- Department of Neurology, School of Mental Health and Neuroscience, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Giuseppe Lauria
- Neuroalgology Unit and Skin Biopsy, Peripheral Neuropathy and Neuropathic Pain Centre, IRCCS Foundation 'Carlo Besta' Neurological Institute, Milan, Italy
| | - Andrew J M Boulton
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK
| | - Handrean Soran
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK
| | - Rayaz A Malik
- Division of Cardiovascular Sciences, Cardiac Centre, Faculty of Biology, Medicine and Health, University of Manchester and NIHR/Wellcome Trust Clinical Research Facility, Manchester, UK.,Research Division, Qatar Foundation, Weill Cornell Medicine-Qatar, Education City, Qatar
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Abstract
PURPOSE OF REVIEW Chronic idiopathic axonal polyneuropathy (CIAP), a common neurological condition, is considered to be a benign neurological condition with a small risk of disability. However, many studies have shown a reduced quality of life and a nonnegligible affection of daily activities in patients with CIAP. Here we summarize recent data about CIAP. RECENT FINDINGS We discuss some of the latest articles regarding risk factors, comorbidities, and possible pathogenic factors regarding CIAP. Patients with chronic polyneuropathy have impaired walking capacity, disturbed balance, and an increased risk of falls. Idiopathic polyneuropathy has a negative impact on activities of daily living. Patients with CIAP may develop plantar ulcers and neuropathic arthropathy. Small fiber involvement may occur, and two recent studies indicate that neuropathic pain is present in about two thirds of the CIAP group. Furthermore, patients with CIAP with neuropathic pain have increased fatigue and poorer emotional well being. SUMMARY Despite the relatively mild motor impairment seen in most patients with CIAP, the condition causes limitations in life with decreased mobility, pain, and affection of basal daily activities. Because the pathogenesis of CIAP in unclear, there is no disease modifying treatment. Further studies regarding pathogenesis, and randomized controlled clinical trials regarding possible treatment options are needed.
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Geisler S. Vincristine- and bortezomib-induced neuropathies - from bedside to bench and back. Exp Neurol 2021; 336:113519. [PMID: 33129841 PMCID: PMC11160556 DOI: 10.1016/j.expneurol.2020.113519] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 10/21/2020] [Accepted: 10/25/2020] [Indexed: 12/11/2022]
Abstract
Vincristine and bortezomib are effective chemotherapeutics widely used to treat hematological cancers. Vincristine blocks tubulin polymerization, whereas bortezomib is a proteasome inhibitor. Despite different mechanisms of action, the main non-hematological side effect of both is peripheral neuropathy that can last long after treatment has ended and cause permanent disability. Many different cellular and animal models of various aspects of vincristine and bortezomib-induced neuropathies have been generated to investigate underlying molecular mechanisms and serve as platforms to develop new therapeutics. These models revealed that bortezomib induces several transcriptional programs in dorsal root ganglia that result in the activation of different neuroinflammatory pathways and secondary central sensitization. In contrast, vincristine has direct toxic effects on the axon, which are accompanied by changes similar to those observed after nerve cut. Axon degeneration following both vincristine and bortezomib is mediated by a phylogenetically ancient, genetically encoded axon destruction program that leads to the activation of the Toll-like receptor adaptor SARM1 (sterile alpha and TIR motif containing protein 1) and local decrease of nicotinamide dinucleotide (NAD+). Here, I describe current in vitro and in vivo models of vincristine- and bortezomib induced neuropathies, present discoveries resulting from these models in the context of clinical findings and discuss how increased understanding of molecular mechanisms underlying different aspects of neuropathies can be translated to effective treatments to prevent, attenuate or reverse vincristine- and bortezomib-induced neuropathies. Such treatments could improve the quality of life of patients both during and after cancer therapy and, accordingly, have enormous societal impact.
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Affiliation(s)
- Stefanie Geisler
- Department of Neurology, Washington University School of Medicine in St. Louis, MO, USA.
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Yamamoto S, Egashira N. Pathological Mechanisms of Bortezomib-Induced Peripheral Neuropathy. Int J Mol Sci 2021; 22:ijms22020888. [PMID: 33477371 PMCID: PMC7830235 DOI: 10.3390/ijms22020888] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 12/12/2022] Open
Abstract
Bortezomib, a first-generation proteasome inhibitor widely used in chemotherapy for hematologic malignancy, has effective anti-cancer activity but often causes severe peripheral neuropathy. Although bortezomib-induced peripheral neuropathy (BIPN) is a dose-limiting toxicity, there are no recommended therapeutics for its prevention or treatment. One of the most critical problems is a lack of knowledge about pathological mechanisms of BIPN. Here, we summarize the known mechanisms of BIPN based on preclinical evidence, including morphological abnormalities, involvement of non-neuronal cells, oxidative stress, and alterations of transcriptional programs in both the peripheral and central nervous systems. Moreover, we describe the necessity of advancing studies that identify the potential efficacy of approved drugs on the basis of pathological mechanisms, as this is a convincing strategy for rapid translation to patients with cancer and BIPN.
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Affiliation(s)
- Shota Yamamoto
- Department of Lipid Signaling, National Center for Global Health and Medicine, Tokyo 162-8655, Japan;
| | - Nobuaki Egashira
- Department of Pharmacy, Kyushu University Hospital, Fukuoka 812-8582, Japan
- Correspondence: ; Tel.: +81-92-642-5920
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Ma J, Stefanoska D, Stone LS, Hildebrand M, van Donkelaar CC, Zou X, Basoli V, Grad S, Alini M, Peroglio M. Hypoxic stress enhances extension and branching of dorsal root ganglion neuronal outgrowth. JOR Spine 2020; 3:e1090. [PMID: 32613165 PMCID: PMC7323469 DOI: 10.1002/jsp2.1090] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/02/2020] [Accepted: 04/07/2020] [Indexed: 12/27/2022] Open
Abstract
It has been shown that painful intervertebral discs (IVDs) were associated with a deeper innervation. However, the effect of the disc's degenerative microenvironment on neuronal outgrowth remains largely unknown. The focus of this study was to determine the influence of hypoxia on dorsal root ganglion (DRG) neurite outgrowth. Toward this aim, the DRG-derived cell line ND7/23 was either directly subjected to 2% or 20% oxygen conditions or exposed to conditioned medium (CM) collected from IVDs cultured under 2% or 20% oxygen. Viability and outgrowth analysis were performed following 3 days of exposure. Results obtained with the cell line were further validated on cultures of rabbit spinal DRG explants and dissociated DRG neurons. Results showed that hypoxia significantly increased neurite outgrowth length in ND7/23 cells, which was also validated in DRG explant and primary cell culture, although hypoxia conditioned IVD did not significantly increase ND7/23 neurite outgrowth. While hypoxia dramatically decreased the outgrowth frequency in explant cultures, it significantly increased collateral sprouting of dissociated neurons. Importantly, the hypoxia-induced decrease of outgrowth frequency at the explant level was not due to inhibition of outgrowth branching but rather to neuronal necrosis. In summary, hypoxia in DRG promoted neurite sprouting, while neuronal necrosis may reduce the density of neuronal outgrowth at the tissue level. These findings may help to explain the deeper neo-innervation found in the painful disc tissue. HIGHLIGHTS Hypoxia promoted elongation and branching of neurite outgrowth at single cell level, but reduced outgrowth density at tissue level, possibly due to hypoxia-induced neuronal necrosis; these findings may help to explain the deeper neo-innervation found in clinically painful tissues.
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Affiliation(s)
- Junxuan Ma
- AO Research Institute DavosDavosSwitzerland
| | - Despina Stefanoska
- AO Research Institute DavosDavosSwitzerland
- Department of Biomedical EngineeringEindhoven University of TechnologyEindhovenThe Netherlands
| | - Laura S. Stone
- Alan Edwards Centre for Research on Pain, Faculty of DentistryMcGill UniversityMontreal, QuebecCanada
| | | | | | - Xuenong Zou
- Department of Spine Surgery, Orthopedic Research InstituteThe First Affiliated Hospital of Sun Yat‐sen UniversityGuangzhouChina
- Guangdong Provincial Key Laboratory of Orthopedics and TraumatologyGuangzhouChina
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